In this first episode, the builders meet Prof. Dai Morgan Evans, the archaeologist who's designed the Roman villa they're attempting to build with just authentic tools and materials. He strips them of most of their modern tools and shows them how to consult the Auguries to make sure the gods approve the site. The first critical phase of the build is the stone work, which includes half-metre-high base walls, which will support a vast oak frame, and full-height bath house walls. So the six men need to hand hew 150 tonnes of sandstone, mix 30 tonnes of ancient lime mortar and build a cart to shift it all about. Thousands of stones will have to be hand shaped, just as the Romans did. It's a steep learning curve as they must master a new range of skills including quarrying stone, making lime mortar and using Roman tools including a Roman surveying device, the groma. Plaster Tim falls in love with the Roman recipe for mortar, carpenter Fred struggles to make a working cart without his power tools and foreman Jim's blunt management style gets on everyone's nerves. One month into the build they are already slipping behind schedule and in desperate need of help. So labourer Ben takes to the local airwaves appealing for volunteers to come to the rescue.

The builders tackle the bath house - the epitome of Roman sophistication. Theirs will boast under floor heating, a plunge pool and steam room. But, in one of the hottest Junes on record, the workmen are finding it hard going. Darren the brickie gets a glow of achievement from his successful brick arch for the bathhouse furnace, and Kevin the plumber delights in his new-found knowledge of the Romans, but the room layout seems dysfunctional to foreman Jim's modern eye. Meanwhile, archaeologist Dai Morgan Evans, the villa's designer, feels they should be making faster progress. To inspire them, Dai takes the builders to see some of the best preserved Roman ruins in the world, at Ephesus in Turkey. Tim the plasterer is particularly overawed by the remains of detailed mosaics and plasterwork in a well-preserved villa. Dai also takes them to a real Turkish bath to experience first hand how the villa's bathhouse would have worked. It proves a memorable, if painful, bonding experience! Back in Wroxeter, the men get to grips with making tubulae, the rectangular clay pipes that will be vital for heating the bathhouse. Dai has to adapt his Roman scaffolding to meet modern health and safety. Fred the chippie scores a success with his authentic Roman windows. And, finally, the first volunteers arrive to help with the build, and they're all women. Foreman Jim soon has them hard at work.

The builders face the most challenging and dangerous phase of the build: constructing the giant timber-frame. First they have to find suitable trees in the local woods from which to construct it. Cutting the trees down with just axes and saws proves to be a major undertaking. But when the timber finally arrives on site, shaping the tree trunks into sections of the wood frame proves even tougher. After a week of hacking and chiselling, foreman Jim is unimpressed with the quality and speed of work and confronts carpenter Fred with his concerns. Meanwhile, plumber Kevin starts to plan the magnificent mosaic that will be the villa's centrepiece. Coming up with a suitable design proves challenging, but a more pressing problem is how to mass produce more than 200,000 tiny tiles with which to make it. With the timber frame finally finished, Jim and his men have to find a way to erect the giant, seven-metre-high sections with nothing but muscle power. It turns out to be Jim's finest hour, and, under his leadership, the huge sections are slowly hauled into place. Finally it's possible to appreciate the sheer size of the villa and, for its designer Dai Morgan Evans, it's an emotional turning point in the project.

The builders have reached the halfway point in their attempt to construct a Roman Villa. The giant wooden frame has been successfully erected and it's a race to get the roof on before the weather breaks. While foreman Jim supervises this, the other builders head off to explore their artistic sides. Plumber Kevin is in charge of creating the villa's mosaic floor and he comes up with an ingenious way of producing the 200,000 tiny tesserae tiles he needs. Ben and Darren get to grips with making the huge phallus that will be mounted on the villa to bring fertility and good luck. Ben further explores his artistic talents when he and Tim learn how create the fresco wall paintings that will adorn the main reception room and feature a heroic portrayal of the six builders.

It's September and the villa is rapidly taking shape. Work gets underway on finishing the bath house and finally plasterer Tim can begin the mammoth task of plastering over 3,000 square metres of walls using an experimental Roman recipe. He is determined to do it all on his own and clashes with foreman Jim, who thinks he should accept help. A new carpenter arrives on site to make the windows and doors for the villa, all without modern power tools, of course. Labourer Ben is given the task of laying his mud bricks and covering the wattle and daub with a mixture that includes animal dung. As usual his work rate fails to impress Jim and even his mates despair of the time it's taking him. Brickie Darren has to master the art of stonemasonry as he sets about creating the villa's impressive entrance columns, chiselled out of solid sandstone blocks. And the bath house nears completion, but a test firing of its under-floor heating system ends in a cloud of thick smoke.

It's October and the final push is on to get the Roman villa completed, before the winter weather makes building impossible. But things aren't going well. The plaster in the showpiece main room won't set, so the painting of the frescoes can't begin. The mosaic tiles won't stick and worrying cracking noises are coming from the hypocaust floor. The builders also discover the unusual materials used by the Romans to finish their floors and make their windows. Long nights are called for as plumber Kevin's mosaic at last begins to take shape and labourer Ben works against the clock to paint his life-size frescoes of the six builders. But the bath-house is completed: the builders put it to the test and plasterer Tim decides to go native and spend a night in the villa to get the full Roman experience. It's been a long haul for the builders, of six months back-breaking work, during which they have used more than 30 tonnes of oak, 150 tonnes of hand cut stone, 3,000 handmade roof tiles and 36 tonnes of lime plaster. As the villa nears completion, its designer, Dai Morgan Evans, has a treat in stall for the men, as he lays on an authentic banquet to re-enact the Roman feast day of Saturnalia.